Java Java: Finding the numbers in an array above the average

AI Thread Summary
The discussion centers around a Java program designed to find numbers above the average in an array of incomes. The user encounters issues with the output, specifically that the range of numbers above the average is not displayed correctly. The code calculates the average and counts how many numbers exceed it but fails to print the actual numbers above the average, instead displaying a memory address due to improper array printing. Suggestions include storing the above-average numbers in a separate array or string for proper output. Additionally, it is noted that the average calculation uses integer division, which may lead to inaccuracies; switching to floating-point division is recommended for more precise results.
Ajmather
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I am attempting to find the numbers above the average number of a set of numbers in an array. I am having trouble understanding why my output for the list of numbers above the average is so...weird. I'd appreciate the help!

My code:

Code:
public class Inequality 
{
	public static void main(String[] args) 
	{
        // list of incomes in thousands
		 int[] income = {2,10, 532, 4, 53, 28, 291, 38, 6, 17, 73, 21};
         int sum = 0;
         int average;
         int aboveAverage = 0;
         
         for (int i = 0;i< income.length;i++)
         {
        	 sum = sum + income[i];
         }
         average = sum/income.length;
         System.out.println("Average of income array: " + average);
         
         for (int i = 0; i < income.length; i++)
         {
        	 if (income[i]>average)
        	 {
        		 aboveAverage++;
        	 }
         }
         System.out.println("There are " + aboveAverage + " numbers above the average.");
         System.out.println("Range of numbers above the average: " + income);
	}
}

My output:

Code:
Average of income array: 89
There are 2 numbers above the average.
Range of numbers above the average: [I@15db9742
 
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It appears to me that what you want to do is when you find a number is above the mean, store it into either an array or better yet, a comma-delimited string. I'm not familiar with Java, but it appear that when you simply attempt to print the income array, you are getting a memory address (like a pointer would behave in C).
 
Ajmather said:
I am attempting to find the numbers above the average number of a set of numbers in an array.
And then do what with them: print them, find their product, or something else? The answer to this determines what data stricture, if any, you need to store these elements.

Ajmather said:
I am having trouble understanding why my output for the list of numbers above the average is so...weird.
There is a reason for a bug report template in many software products. You are supposed to write the expected behavior and the actual behavior. What seems weird to you may seem natural to another person.

First, I don't see where you print the list of numbers above the average. I see where you attempt to print the whole array. I agree with Mark that arrays are not supposed to be printed in this way, namely, using a single call to [m]System.out.println()[/m].

Second, currently you are using integer division in [m]sum/income.length[/m], which rounds down the result. You may want to use floating-point division by defining [m]average[/m] to be a [m]float[/m] or [m]double[/m] and using [m](float)sum/income.length[/m]. Alternatively, you can declare [m]sum[/m] as a [m]float[/m].
 
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